def str_com(strr):
    try:
        str(strr)
        lst = []
        for i in strr:
            if i not in lst:
                lst.append(i)
            else:
                print(f'第一个重复的字符是{i}')
                break
    except EOFError as ee:
        print('请输入字符串')


str_com(input('请输入字符串'))
